At present, the GOA circuit usually uses a top gate structure of the thin film transistor (Top gate IGZO TFT), wherein the source and gate and the drain and gate of the top gate structure of the thin film transistor are not overlapping parts, so the thin film transistor parasitic capacitance is small.
Since the semiconductor layer of the thin film transistor has no gate for light blocking, the semiconductor layer is seriously affected by the light, thereby causing the electrical failure of the semiconductor layer.